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The article discusses how Steam, a gaming platform, protects its game servers from Distributed Denial of Service (DDoS) attacks by using a virtual private network composed of hundreds of global relays and data centers. This network is designed to be attacked but has yet to be successfully breached. The system was originally implemented as a way to protect Dota game servers, but it has since grown to provide faster connectivity and lower ping times for all Steam customers, regardless of the game they are playing. The SDR network delivers millions of packets and gigabytes of data per second, with relays in 31 data centers capable of handling over 5 terabytes of data.